Si含量对9%Cr铁素体马氏体钢微观结构和力学性能的影响  

Effect of Si Content on Microstructure and Mechanical Property of 9%Cr Ferrite Martensitic Steel

作　　者：周军[1] 邱绍宇[1] 邱日盛[2] 曾文[2] 陈勇[1] 肖军[1] 王浩[1] 潘钱付[1] 杨灿湘[1] 卓洪[1] ZHOU Jun;QIU Shaoyu;QIU Risheng;ZENG Wen;CHEN Yong;XIAO Jun;WANG Hao;PAN Qianfu;YANG Canxiang;ZHUO Hong(Department of Nuclear Fuel and Material,Nuclear Power Institute of China,Chengdu 610041,China;College of Materials Science and Engineering,Chongqing University,Chongqing 400045,China)

机构地区：[1]中国核动力研究设计院核燃料元件及材料研究所,四川成都610041 [2]重庆大学材料科学与工程学院,重庆400045

出　　处：《原子能科学技术》2022年第3期520-528,共9页Atomic Energy Science and Technology

基　　金：中核集团集中研发项目。

摘　　要：铁素体马氏体(F/M)钢是铅冷快堆堆芯的主要候选材料之一,提高Si含量可提高其抗腐蚀性能,但影响其微观结构和力学性能。为研发兼顾力学性能和抗腐蚀性能的高Si含量F/M钢,本文对Si含量(质量分数为0.34%、0.61%、0.80%、0.98%和1.20%)对9%Cr F/M钢微观结构和力学性能的影响进行了研究。结果显示,室温下通过正火(1050℃,0.5 h,空冷)+回火(760℃,1.5 h,空冷)热处理制备的F/M钢均为全马氏体组织。钢的屈服强度和抗拉强度均随Si含量的增加而增加。Si含量对钢的组织及冲击性能的影响可分为两个阶段,当F/M钢中Si含量为0.34%~0.80%时,其组织、冲击性能变化很小;Si含量为0.98%~1.20%时,F/M钢中的第二相尺寸、数量增加,沿马氏体板条界面析出少量的Laves相,F/M钢的冲击韧性降低。本研究9%Cr F/M钢中Si元素的最优添加量应低于0.8%,使钢在保持较高强度的同时兼具良好的韧性。The 9%-12%Cr ferritic Martensitic(F/M)steel has the advantages of excellent creep performance at high temperature,remarkable irradiation resistance,high thermal conductivity,small thermal expansion coefficient,good economy and mature engineering application.The 9%-12%Cr F/M steel is one of the main candidate materials for lead-cooled fast reactor core.The corrosion resistances of liquid Pb and Bi were improved by increasing Si content,and the microstructure and mechanical properties of F/M steel,especially the plasticity of F/M steel were affected simultaneously.The 5 types of 9%Cr F/M steels with Si content(mass fractions of 0.34%,0.61%,0.80%,0.98%and 1.20%)were designed and prepared to develop the mechanical properties and corrosion resistance of the high Si content F/M steel.The samples of 9%Cr F/M steels were named Z1-Z5 according to different Si contents.And the sheet metal samples with thickness of 8 mm were prepared by vacuum melting,forging,hot rolling and final heat treatment.Optical microscope,scanning electron microscope,transmission electron microscope and energy spectrometer were used to characterize the microstructure of F/M steel matrix,M;C;and Laves phase.The room temperature tensile properties and room temperature impact properties of F/M steel were tested in accordance with national standards of China.In result,the microstructure of F/M steel prepared by normalizing(1050℃,0.5 h,air cooling)and subsequently heated(760℃,1.5 h,air cooling)at room temperature is all Martensitic.The grain size and Martensite lath width are not affected by the Si content.The yield strength and tensile strength of F/M steel at room temperature both increase as the increase of Si content.The influence of Si content on the structure and room temperature impact properties of F/M steel is divided into two stages.When the Si content in the steel is 0.34%-0.80%(mass fraction),the structure and room temperature impact properties of the steel change little.When the Si content in the steel is 0.98%-1.20%,the size and quanti

关 键 词：9%Cr铁素体马氏体钢 SI含量 拉伸性能 冲击性能 析出相 

分 类 号：TL34[核科学技术—核技术及应用]